Definition of A H1N1

A H1N1 is a subtype of flu virus and is the official name given by the World Health Organisation to the 2009 pandemic. There are many variants of H1N1s. The pandemic virus is also commonly called swine flu, despite objections by the Organisation for Animal Health, which argues there is no evidence that it spread to humans from pigs. Based on information to date, the pandemic strain is mild: it is no more lethal than seasonal flu, but in contrast those most affected are young people rather than the elderly. [1]